So yesterday I got a Cel again. Pulled the code and got p0452 FTP sensor to low, cleared it and drive to work today. No CEL until I made a few stops on my way home. Then I get a CEL pull the. Ode and get p0453. FTP sensor voltage to high. WTF?

In case it matters it was raining on my way home. I also. Price a rough idle and so desire shifting. Also I remembered today that when I changed the Intake manifold gasket I pinched the hose that connects the MAP sensor to the intake. It is a special molded t so I fixed it with a little black RTV. I'm throwing that out there because the ECU gets a reference value for tank pressure from the MAP.

Any ideas? Just replace the rigged tubing and the FTP sensor?

Thanks!

Is this the only issue, or is it still oil canning?

Only issue. Oil canning is gone. Well I did notice a slightly rough idle since the CEL started coming back.

Fix the easy stuff first (the tube) and see what you get.

I am glad the oil canning is gone. I suspect the after market gas cap was the culprit, but I can't be entirely certain.

I'll get the tube from the dealer tomorrow and see where that goes.

I did put the aftermarket cap back on after I replaced the purge valve just to see what would happen. The oil canning never came back. When the CEL came back I put the OEM cap back on and cleared the CEL. Within the next 15 miles the CEL p0453 came back. So I don't think the cap had any effect.

Ill post back results of replacing the tube.

Something else I have realized. It threw a P0452 with a quarter tank of gas. I filled up today and then got the p0453 code. Not sure if that matters or not.

could still be the sensor itself but i would do as you are and track one thing at a time, get the tubes right and go from there.

as i said the cap only comes into play when the vent valve isnt functioning it can vent pressure when sitting there but your problem was vacuum when the car is running cap is sealed at that point

So I picked up the MAP tube from the dealer last Wed and installed. No Change. Still trowing code p0452 and p0453.

I did notice that with a full tank I get code p0453, voltage to high. And with a half tank or less I get p0452, voltage to low. So I picked up a FTP sensor this morning and installed it. It wasn't to bad. I just took off the tank straps and lowered the tank enough to see the sending unit. I was able to remove the old sensor and install the new one. Took 10 minutes max. I am clearing the codes right now and will test drive shortly.

I did notice that the sensors had a number painted on them from the manufacturer. This number was different on the old sensor and the new. Maybe the sending unit had the incorrect sensor installed when it was manufactered? They are both BWD sensors.

I'll update with the results.

Keep us posted. I am curious to see if this fixed it.

So far so good. Cleared the CEL after replacing the FTP sensor and it hasn't returned. I filled the tank up today which usually always sets a CEL. But this time it did not.

Hopefully got this fixed. FINALLY!